An art dealer famous for representing artists such as Picasso, Braque, and Matisse. He began his career in his father's antiques business, and worked in England (1902–05) before returning to Paris to open an art gallery (1911). The gallery was successful enough that he opened another store in England (1935). He emigrated to the U.S. in 1940 to escape the war, and opened a New York gallery in which he represented contemporary American and European artists.